Liberals, it’s said, are trusting to a fault, easily suckered by people of bad intent. Conservatives, it’s said, are resistant to change—and not just resistant, but fearful, and very well aware of the threats that changes to the status quo involve.

These are matters of character—that old-fashioned word. Increasingly, newfangled neuroscientists are finding, they are also matters of brain chemistry. Conservatives and liberals have different beliefs, to be sure, but also different ways of processing the information that yields or confirms those beliefs.

Discover magazine science blogger Chris Mooney is both an unabashed liberal and a science reporter of many years’ standing. Working his beats, he found himself wondering why, when presented with the same data, people with views on the left and right came to widely different conclusions about such things as climate change and environmental pollution. “Like many liberals,” he says, “I grew increasingly frustrated by the denial of science and fact coming from the political right in the United States, and by the inability of factual or reasoned arguments to change minds. So finally my only recourse was to explore what science itself has to say about how the left and right process information differently, and what kind of communication remains possible once we look at the real roots of our political differences.”

The result of that exploration is his new book The Republican Brain. Britannica contributing editor Gregory McNamee caught up with Chris Mooney to talk about his work and findings.

Britannica: To judge by your book and the extensive scientific research it reports, the conservative, or Republican, brain would indeed seem to be wired differently from the liberal, or Democratic, one. What are some of the principal differences between them, and in their resulting ways of thinking?

Chris Mooney: Well, let’s be careful with the word “wired.” To a lot of people, it implies that we lack any choice or are unable to change our political views. That’s a bit more deterministic than the evidence warrants, because people can and do change their minds. It’s important to get that on the table.

That said, there is a vast body of research from the field of psychology showing differences in personality and psychological needs between the average liberal and the average conservative. Most broadly, liberals seem to be more open to new experiences, to trying new things, and more tolerant of ambiguity, uncertainty, nuance and change. Conservatives are less open, with all that implies, but more conscientious, meaning they appreciate order and structure in their lives—being on time, driving to work the same way every day, keeping organized, and so on.

It was probably inevitable that eventually researchers would try to find more basic physical correlates for these psychological differences. And they haven’t just done this in the brain, by the way. They’ve done it by tracking physiological or bodily responses to various stimuli. Conservatives show more skin conductance when shown threatening images, for instance (an indicator of sympathetic nervous system arousal), and their eyes dart toward them faster and stay there longer.

All of this stuff, by the way, is automatic. It is not under your conscious control.

Then there’s the brain. Here, the research is tentative but suggestive. Several studies have correlated conservatism with the amygdala—the brain’s automatic fear and threat center—and liberalism with the anterior cingulate cortex, an error-detecting region involved in making us change a habitual pattern of behavior. The research seems to suggest that small variations in these regions or how they are used may impel our political differences.

So, yes: It is starting to look like there may be actual left–right brain differences, of a sort that are easily measurable. But we shouldn’t overemphasize the brain studies alone. What’s important is that they are part of a much broader body of evidence, across scientific fields, showing that liberals and conservatives just process information differently, on average, and probably go through life experiencing the world differently. And this may be at the root of our political and even our factual divides.

Chris Mooney, 2011. Credit: courtesy of Chris Mooney

Britannica: If you were designing a brain science-based campaign against a Republican candidate, what might some of its rhetoric or strategies be? Similarly, how might a Republican campaign against a Democratic opponent, again based on science?

Chris Mooney: One part of this is easy. The conservative fares best if he or she appeals to fear. All the research shows that at times of great stress or threat, conservatives are at an advantage politically—after 9/11, for instance.

This sensitivity to threat is probably why. At times of fear and threat, people don’t have any time or interest for the wonky, nuanced policies that liberals like to propose. They’re focused on something much, much more immediate and visceral. And they like strong and decisive leaders.

Liberals fare best at a different time—when they can excite widespread emotions of empathy in the public, such as happened after Hurricane Katrina. So that is the emotion that a liberal candidate wants to evoke.

Britannica: Where do greens, libertarians, independents, and other outliers from the two-party system fit into all this? Are their brains different, too, or just their politics?

Chris Mooney: Everybody’s brain is a little different. It’s important to emphasize that not every liberal is a psychological liberal, nor is every conservative a psychological conservative. The psychological traits that separate left and right describe average tendencies, but there will be many people who are above or below the average, on both sides of the aisle.

Greens have a broadly liberal psychology. As for independents, I spend a section of the book on them. They’re tricky.

There are both disengaged independents, who simply aren’t following politics closely enough to take a side, and then there are well-informed moderates or centrists. These are two very different groups. The disengaged independents may be psychologically quite liberal or conservative, but not attuned enough to see how their values and psychologies match up with the current parties. By contrast, the well-informed moderates or centrists might have a blend of typically conservative and typically liberal traits, and it feels natural to them to split the difference.

And then there are libertarians—theoretically, those who are economically conservative but socially liberal. They are a smaller group, but the research shows that at least for economic conservatives, they, too, tend to be less open to new experiences, and more conscientious.

Britannica: Can this neurological way of looking at political differences be applied to other countries? Are people studying up on such things at Foggy Bottom and Langley?

Chris Mooney: One of the most prominent recent left–right brain studies was done in the UK. And the psychology-of-ideology research that all of this is based on has been carried out across countries. However, it has naturally been much easier to do the research in European democracies than to do it in, say, communist countries. And none of the researchers that I’m reading seem to have much of a handle on Asian countries.

That said, in Europe and the United States, left and right do seem to share quite a great deal, even though there are also significant cultural and political differences.

Basically, I think there is enough evidence at this point to propose that political ideology is an outgrowth of basic human nature; that it emerges from some combination of personality and moral values; and that these, in turn, are rooted in more basic traits, but also inevitably shaped by experience.

There is such an intellectual ferment in this area now that in ten years, I am sure we’ll know a ton more. But already, it seems clear that ideology is the reflection of something much deeper than our conscious ideas and choices about how we think society should be structured.

Britannica: Your reporting has implications in many areas. Let’s concentrate on two closely related ones: education and science. What are the implications of the two political brains, so to speak, when it comes to governmental funding for them?

Chris Mooney: Interesting question. First, the scientific establishment in the United States is strongly liberal, and conservatives know that very well. And I argue in the book that liberals and scientists are closely aligned for deep psychological reasons—both groups are much more comfortable with ambiguity, nuance, uncertainty, and change. Both groups are intellectual explorers and innovators. That sort of makes them natural allies.

However, it is very important that science not get politicized to the point that conservatives come to think of it as the enemy and seek to cut its funding. Rather, conservatives, to my mind, should take the view that science and the academy are naturally liberal parts of society, and that’s just fine, because it’s part of who human beings are, just as conservatism is also part of who human beings are.

With respect to education—higher education, at least—the story is very similar. Universities are like a playground for people who are open to new experiences and want to try out new things, including new ideas—in short, liberals. Rick Santorum attacked universities during the campaign, but he did so based on a clichéd idea that universities make you liberal. No: Universities appeal to the liberal side of human nature, which will always be there. You might almost think of it as tradition.